Vacuum adiabatic body, fabrication method for the vacuum adiabatic body, porous substance package, and refrigerator

ABSTRACT

A vacuum adiabatic body, a method for fabricating a vacuum adiabatic body, a porous substance package, and a refrigerator including a vacuum adiabatic body and a porous substance package are provided. The vacuum adiabatic body may include a first plate, a second plate, a seal, a support, a heat resistance device, and an exhaust port. The support may include a porous substance and a film made of a resin material, the film configured to accommodate the porous substance therein. Accordingly, it may be possible to provide a vacuum adiabatic body through an inexpensive process.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation Application of U.S. National Stageapplication Ser. No. 15/749,179 filed Jan. 31, 2018 under 35 U.S.C. §371 of PCT Application No. PCT/KR2016/008470, filed Aug. 1, 2016, whichclaims priority to Korean Patent Application No. 10-2015-0109726, filedAug. 3, 2015, whose entire disclosures are hereby incorporated byreference.

BACKGROUND 1. Field

The present disclosure relates to a vacuum adiabatic body, a fabricationmethod for the vacuum adiabatic body, a porous substance package, and arefrigerator.

2. Background

A vacuum adiabatic body is a product for suppressing heat transfer byvacuuming the interior of a body thereof. The vacuum adiabatic body canreduce heat transfer by convection and conduction, and hence is appliedto heating apparatuses and refrigerating apparatuses. In a typicaladiabatic method applied to a refrigerator, although it is differentlyapplied in refrigeration and freezing, a foam urethane adiabatic wallhaving a thickness of about 30 cm or more is generally provided.However, the internal volume of the refrigerator is therefore reduced.

In order to increase the internal volume of a refrigerator, there is anattempt to apply a vacuum adiabatic body to the refrigerator.

First, Korean Patent No. 10-0343719 (Reference Document 1) of thepresent applicant has been disclosed. According to Reference Document 1,there is disclosed a method in which a vacuum adiabatic panel isprepared and then built in walls of a refrigerator, and the exterior ofthe vacuum adiabatic panel is finished with a separate molding such asStyrofoam (polystyrene). According to the method, additional foaming isnot required, and the adiabatic performance of the refrigerator isimproved. However, fabrication cost is increased, and a fabricationmethod is complicated. As another example, a technique of providingwalls using a vacuum adiabatic material and additionally providingadiabatic walls using a foam filling material has been disclosed inKorean Patent Publication No. 10-2015-0012712 (Reference Document 2).According to Reference Document 2, fabrication cost is increased, and afabrication method is complicated.

As another example, there is an attempt to fabricate all walls of arefrigerator using a vacuum adiabatic body that is a single product. Forexample, a technique of providing an adiabatic structure of arefrigerator to be in a vacuum state has been disclosed in U.S. PatentLaid-Open Publication No. US 2004/0226956 A1 (Reference Document 3).

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments will be described in detail with reference to thefollowing drawings in which like reference numerals refer to likeelements wherein:

FIG. 1 is a perspective view of a refrigerator according to anembodiment.

FIG. 2 is a view schematically showing a vacuum adiabatic body used in amain body and a door of the refrigerator.

FIG. 3 is a view showing various embodiments of an internalconfiguration of a vacuum space part.

FIG. 4 is a view showing various embodiments of conductive resistancesheets and peripheral parts thereof.

FIG. 5 illustrates graphs showing changes in adiabatic performance andchanges in gas conductivity with respect to vacuum pressures by applyinga simulation.

FIG. 6 illustrates graphs obtained by observing, over time and pressure,a process of exhausting the interior of the vacuum adiabatic body when asupporting unit is used.

FIG. 7 illustrates graphs obtained by comparing vacuum pressures and gasconductivities.

FIG. 8 is a sectional view of a vacuum adiabatic body according to anembodiment, which schematically shows the vacuum adiabatic bodyavailable for the main body of the refrigerator.

FIG. 9 is a view sequentially illustrating a fabrication method of thevacuum adiabatic body when a porous substance is used.

FIG. 10 is a sectional view of a porous substance package temporarilyvacuumed before being mounted in the vacuum adiabatic body.

FIG. 11 is a view illustrating a fabrication apparatus of the poroussubstance package.

FIG. 12 is a view showing an embodiment of a punching mechanism.

FIGS. 13 and 14 are view showing another embodiment of the poroussubstance package.

DETAILED DESCRIPTION

Reference will now be made in detail to the embodiments of the presentdisclosure, examples of which are illustrated in the accompanyingdrawings.

In the following detailed description of the preferred embodiments,reference is made to the accompanying drawings that form a part hereof,and in which is shown by way of illustration specific preferredembodiments in which the disclosure may be practiced. These embodimentsare described in sufficient detail to enable those skilled in the art topractice the disclosure, and it is understood that other embodiments maybe utilized and that logical structural, mechanical, electrical, andchemical changes may be made without departing from the spirit or scopeof the disclosure. To avoid detail not necessary to enable those skilledin the art to practice the disclosure, the description may omit certaininformation known to those skilled in the art. The following detaileddescription is, therefore, not to be taken in a limiting sense.

In the following description, the term ‘vacuum pressure’ means a certainpressure state lower than atmospheric pressure. In addition, theexpression that a vacuum degree of A is higher than that of B means thata vacuum pressure of A is lower than that of B.

FIG. 1 is a perspective view of a refrigerator according to anembodiment.

Referring to FIG. 1 , the refrigerator 1 includes a main body 2 providedwith a cavity 9 capable of storing storage goods and a door 3 providedto open/close the main body 2. The door 3 may be rotatably or movablydisposed to open/close the cavity 9. The cavity 9 may provide at leastone of a refrigerating chamber and a freezing chamber.

Parts constituting a freezing cycle in which cold air is supplied intothe cavity 9 may be included. Specifically, the parts include acompressor 4 for compressing a refrigerant, a condenser 5 for condensingthe compressed refrigerant, an expander 6 for expanding the condensedrefrigerant, and an evaporator 7 for evaporating the expandedrefrigerant to take heat. As a typical structure, a fan may be installedat a position adjacent to the evaporator 7, and a fluid blown from thefan may pass through the evaporator 7 and then be blown into the cavity9. A freezing load is controlled by adjusting the blowing amount andblowing direction by the fan, adjusting the amount of a circulatedrefrigerant, or adjusting the compression rate of the compressor, sothat it is possible to control a refrigerating space or a freezingspace.

FIG. 2 is a view schematically showing a vacuum adiabatic body used inthe main body and the door of the refrigerator. In FIG. 2 , a mainbody-side vacuum adiabatic body is illustrated in a state in which topand side walls are removed, and a door-side vacuum adiabatic body isillustrated in a state in which a portion of a front wall is removed. Inaddition, sections of portions at conductive resistance sheets areschematically illustrated for convenience of understanding.

Referring to FIG. 2 , the vacuum adiabatic body includes a first platemember or first plate 10 for providing a wall of a low-temperaturespace, a second plate member or second plate 20 for providing a wall ofa high-temperature space, a vacuum space part or vacuum space 50 definedas a gap part or gap between the first and second plate members 10 and20. Also, the vacuum adiabatic body includes the conductive resistancesheets 60 and 63 for preventing heat conduction between the first andsecond plate members 10 and 20. A sealing part or seal 61 for sealingthe first and second plate members 10 and 20 is provided such that thevacuum space part 50 is in a sealing or sealed state. When the vacuumadiabatic body is applied to a refrigerating or heating cabinet, thefirst plate member 10 may be referred to as an inner case, and thesecond plate member 20 may be referred to as an outer case. A machinechamber 8 in which parts providing a freezing cycle are accommodated isplaced at a lower rear side of the main body-side vacuum adiabatic body,and an exhaust port 40 for forming a vacuum state by exhausting air inthe vacuum space part 50 is provided at any one side of the vacuumadiabatic body. In addition, a pipeline 64 passing through the vacuumspace part 50 may be further installed so as to install a defrostingwater line and electric lines.

The first plate member 10 may define at least one portion of a wall fora first space provided thereto. The second plate member 20 may define atleast one portion of a wall for a second space provided thereto. Thefirst space and the second space may be defined as spaces havingdifferent temperatures. Here, the wall for each space may serve as notonly a wall directly contacting the space but also a wall not contactingthe space. For example, the vacuum adiabatic body of the embodiment mayalso be applied to a product further having a separate wall contactingeach space.

Factors of heat transfer, which cause loss of the adiabatic effect ofthe vacuum adiabatic body, are heat conduction between the first andsecond plate members 10 and 20, heat radiation between the first andsecond plate members 10 and 20, and gas conduction of the vacuum spacepart 50.

Hereinafter, a heat resistance unit or device provided to reduceadiabatic loss related to the factors of the heat transfer will beprovided. Meanwhile, the vacuum adiabatic body and the refrigerator ofthe embodiment do not exclude that another adiabatic means is furtherprovided to at least one side of the vacuum adiabatic body. Therefore,an adiabatic means using foaming or the like may be further provided toanother side of the vacuum adiabatic body.

FIG. 3 is a view showing various embodiments of an internalconfiguration of the vacuum space part.

First, referring to FIG. 3 a , the vacuum space part 50 is provided in athird space having a different pressure from the first and secondspaces, preferably, a vacuum state, thereby reducing adiabatic loss. Thethird space may be provided at a temperature between the temperature ofthe first space and the temperature of the second space. Since the thirdspace is provided as a space in the vacuum state, the first and secondplate members 10 and 20 receive a force contracting in a direction inwhich they approach each other due to a force corresponding to apressure difference between the first and second spaces. Therefore, thevacuum space part 50 may be deformed in a direction in which it isreduced. In this case, adiabatic loss may be caused due to an increasein amount of heat radiation, caused by the contraction of the vacuumspace part 50, and an increase in amount of heat conduction, caused bycontact between the plate members 10 and 20.

A supporting unit 30 may be provided to reduce the deformation of thevacuum space part 50. The supporting unit 30 includes bars 31. The bars31 may extend in a direction substantially vertical to the first andsecond plate members 10 and 20 so as to support a distance between thefirst and second plate members 10 and 20. A support plate 35 may beadditionally provided to at least one end of the bar 31. The supportplate 35 connects at least two bars 31 to each other, and may extend ina direction horizontal to the first and second plate members 10 and 20.The support plate 35 may be provided in a plate shape, or may beprovided in a lattice shape such that its area contacting the first orsecond plate member 10 or 20 is decreased, thereby reducing heattransfer. The bars 31 and the support plate 35 are fixed to each otherat at least one portion, to be inserted together between the first andsecond plate members 10 and 20. The support plate 35 contacts at leastone of the first and second plate members 10 and 20, thereby preventingdeformation of the first and second plate members 10 and 20. Inaddition, based on the extending direction of the bars 31, a totalsectional area of the support plate 35 is provided to be greater thanthat of the bars 31, so that heat transferred through the bars 31 can bediffused through the support plate 35.

A material of the supporting unit 30 may include a resin selected fromthe group consisting of PC, glass fiber PC, low outgassing PC, PPS, andLCP so as to obtain high compressive strength, low outgassing and waterabsorptance, low thermal conductivity, high compressive strength at hightemperature, and excellent machinability.

A radiation resistance sheet 32 for reducing heat radiation between thefirst and second plate members 10 and 20 through the vacuum space part50 will be described. The first and second plate members 10 and 20 maybe made of a stainless material capable of preventing corrosion andproviding a sufficient strength. The stainless material has a relativelyhigh emissivity of 0.16, and hence a large amount of radiation heat maybe transferred. In addition, the supporting unit 30 made of the resinhas a lower emissivity than the plate members, and is not entirelyprovided to inner surfaces of the first and second plate members 10 and20. Hence, the supporting unit 30 does not have great influence onradiation heat. Therefore, the radiation resistance sheet 32 may beprovided in a plate shape over a majority of the area of the vacuumspace part 50 so as to concentrate on reduction of radiation heattransferred between the first and second plate members 10 and 20. Aproduct having a low emissivity may be preferably used as the materialof the radiation resistance sheet 32. In an embodiment, an aluminum foilhaving an emissivity of 0.02 may be used as the radiation resistancesheet 32. Since the transfer of radiation heat cannot be sufficientlyblocked using one radiation resistance sheet, at least two radiationresistance sheets 32 may be provided at a certain distance so as not tocontact each other. In addition, at least one radiation resistance sheetmay be provided in a state in which it contacts the inner surface of thefirst or second plate member 10 or 20.

Referring to FIG. 3 b , the distance between the plate members ismaintained by the supporting unit 30, and a porous substance 33 may befilled in the vacuum space part 50. The porous substance 33 may have ahigher emissivity than the stainless material of the first and secondplate members 10 and 20. However, since the porous substance 33 isfilled in the vacuum space part 50, the porous substance 33 has a highefficiency for resisting the radiation heat transfer.

In this embodiment, the vacuum adiabatic body can be fabricated withoutusing the radiation resistance sheet 32.

Referring to FIG. 3 c , the supporting unit 30 maintaining the vacuumspace part 50 is not provided. Instead of the supporting unit 30, theporous substance 33 is provided in a state in which it is surrounded bya film 34. In this case, the porous substance 33 may be provided in astate in which it is compressed so as to maintain the gap of the vacuumspace part 50. The film 34 is made of, for example, a PE material, andmay be provided in a state in which holes are formed therein.

In this embodiment, the vacuum adiabatic body can be fabricated withoutusing the supporting unit 30. In other words, the porous substance 33can simultaneously serve as the radiation resistance sheet 32 and thesupporting unit 30.

A case where the porous substance 33 is filled in the vacuum space part50 will be described in detail later.

FIG. 4 is a view showing various embodiments of the conductiveresistance sheets and peripheral parts thereof. Structures of theconductive resistance sheets are briefly illustrated in FIG. 2 , butwill be understood in detail with reference to FIG. 4 .

First, a conductive resistance sheet proposed in FIG. 4 a may bepreferably applied to the main body-side vacuum adiabatic body.Specifically, the first and second plate members 10 and 20 are to besealed so as to vacuum the interior of the vacuum adiabatic body. Inthis case, since the two plate members have different temperatures fromeach other, heat transfer may occur between the two plate members. Aconductive resistance sheet 60 is provided to prevent heat conductionbetween two different kinds of plate members.

The conductive resistance sheet 60 may be provided with sealing parts 61at which both ends of the conductive resistance sheet 60 are sealed todefine at least one portion of the wall for the third space and maintainthe vacuum state. The conductive resistance sheet 60 may be provided asa thin foil in units of micrometers so as to reduce the amount of heatconducted along the wall for the third space. The sealing parts 61 maybe provided as welding parts. That is, the conductive resistance sheet60 and the plate members 10 and 20 may be fused to each other. In orderto cause a fusing action between the conductive resistance sheet 60 andthe plate members 10 and 20, the conductive resistance sheet 60 and theplate members 10 and 20 may be made of the same material, and astainless material may be used as the material. The sealing parts 61 arenot limited to the welding parts, and may be provided through a processsuch as caulking. The conductive resistance sheet 60 may be provided ina curved shape. Thus, a heat conduction distance of the conductiveresistance sheet 60 is provided longer than the linear distance of eachplate member, so that the amount of heat conduction can be furtherreduced.

A change in temperature occurs along the conductive resistance sheet 60.Therefore, in order to block heat transfer to the exterior of theconductive resistance sheet 60, a shielding part or shield 62 may beprovided at the exterior of the conductive resistance sheet 60 such thatan adiabatic action occurs. In other words, in the refrigerator, thesecond plate member 20 has a high temperature and the first plate member10 has a low temperature. In addition, heat conduction from hightemperature to low temperature occurs in the conductive resistance sheet60, and hence the temperature of the conductive resistance sheet 60 issuddenly changed. Therefore, when the conductive resistance sheet 60 isopened to the exterior thereof, heat transfer through the opened placemay seriously occur. In order to reduce heat loss, the shielding part 62is provided at the exterior of the conductive resistance sheet 60. Forexample, when the conductive resistance sheet 60 is exposed to any oneof the low-temperature space and the high-temperature space, theconductive resistance sheet 60 does not serve as a conductive resistoras well as the exposed portion thereof, which is not preferable.

The shielding part 62 may be provided as a porous substance contactingan outer surface of the conductive resistance sheet 60. The shieldingpart 62 may be provided as an adiabatic structure, e.g., a separategasket, which is placed at the exterior of the conductive resistancesheet 60. The shielding part 62 may be provided as a portion of thevacuum adiabatic body, which is provided at a position facing acorresponding conductive resistance sheet 60 when the main body-sidevacuum adiabatic body is closed with respect to the door-side vacuumadiabatic body. In order to reduce heat loss even when the main body 2and the door 3 are opened, the shielding part 62 may be preferablyprovided as a porous substance or a separate adiabatic structure.

A conductive resistance sheet proposed in FIG. 4 b may be preferablyapplied to the door-side vacuum adiabatic body. In FIG. 4 b , portionsdifferent from those of FIG. 4 a are described in detail, and the samedescription is applied to portions identical to those of FIG. 4 a . Aside frame 70 is further provided at an outside of the conductiveresistance sheet 60. A part for sealing between the door and the mainbody, an exhaust port necessary for an exhaust process, a getter port 41for vacuum maintenance, and the like may be placed on the side frame 70.This is because the mounting of parts is convenient in the mainbody-side vacuum adiabatic body, but the mounting positions of parts arelimited in the door-side vacuum adiabatic body.

In the door-side vacuum adiabatic body, it is difficult to place theconductive resistance sheet 60 at a front end portion of the vacuumspace part, i.e., a corner side portion of the vacuum space part. Thisis because, unlike the main body, a corner edge portion of the door isexposed to the exterior. More specifically, if the conductive resistancesheet 60 is placed at the front end portion of the vacuum space part,the corner edge portion of the door is exposed to the exterior, andhence there is a disadvantage in that a separate adiabatic part shouldbe configured so as to heat-insulate the conductive resistance sheet 60.

A conductive resistance sheet proposed in FIG. 4 c may be preferablyinstalled in the pipeline passing through the vacuum space part. In FIG.4 c , portions different from those of FIGS. 4 a and 4 b are describedin detail, and the same description is applied to portions identical tothose of FIGS. 4 a and 4 b . A conductive resistance sheet having thesame shape as that of FIG. 4 a , preferably, a wrinkled or foldedconductive resistance sheet 63 may be provided at a peripheral portionof the pipeline 64. Accordingly, a heat transfer path can be lengthened,and deformation caused by a pressure difference can be prevented. Inaddition, a separate shielding part may be provided to improve theadiabatic performance of the conductive resistance sheet.

A heat transfer path between the first and second plate members 10 and20 will be described with reference back to FIG. 4 a . Heat passingthrough the vacuum adiabatic body may be divided into surface conductionheat {circle around (1)} conducted along a surface of the vacuumadiabatic body, more specifically, the conductive resistance sheet 60,supporter conduction heat {circle around (2)} conducted along thesupporting unit 30 provided inside the vacuum adiabatic body, gasconduction heat {circle around (3)} conducted through an internal gas inthe vacuum space part, and radiation transfer heat {circle around (4)}transferred through the vacuum space part.

The transfer heat may be changed depending on various design dimensions.For example, the supporting unit may be changed such that the first andsecond plate members 10 and 20 can endure a vacuum pressure withoutbeing deformed, the vacuum pressure may be changed, the distance betweenthe plate members may be changed, and the length of the conductiveresistance sheet may be changed. The transfer heat may be changeddepending on a difference in temperature between the spaces (the firstand second spaces) respectively provided by the plate members. In theembodiment, a preferred configuration of the vacuum adiabatic body hasbeen found by considering that its total heat transfer amount is smallerthan that of a typical adiabatic structure formed by foamingpolyurethane. In a typical refrigerator including the adiabaticstructure formed by foaming the polyurethane, an effective heat transfercoefficient may be proposed as 19.6 mW/mK.

By performing a relative analysis on heat transfer amounts of the vacuumadiabatic body of the embodiment, a heat transfer amount by the gasconduction heat {circle around (3)} can become smallest. For example,the heat transfer amount by the gas conduction heat {circle around (3)}may be controlled to be equal to or smaller than 4% of the total heattransfer amount. A heat transfer amount by solid conduction heat definedas a sum of the surface conduction heat {circle around (1)} and thesupporter conduction heat {circle around (2)} is largest. For example,the heat transfer amount by the solid conduction heat may reach 75% ofthe total heat transfer amount. A heat transfer amount by the radiationtransfer heat {circle around (4)} is smaller than the heat transferamount by the solid conduction heat but larger than the heat transferamount of the gas conduction heat {circle around (3)}. For example, theheat transfer amount by the radiation transfer heat {circle around (4)}may occupy about 20% of the total heat transfer amount.

According to such a heat transfer distribution, effective heat transfercoefficients (eK: effective K) (W/mK) of the surface conduction heat{circle around (1)}, the supporter conduction heat {circle around (2)},the gas conduction heat {circle around (3)}, and the radiation transferheat {circle around (4)} may have an order of Math Figure 1.eK_(solid conduction heat)>eK_(radiation transfer heat)>eK_(gas conduction heat)  [Math.1]

Here, the effective heat transfer coefficient (eK) is a value that canbe measured using a shape and temperature differences of a targetproduct. The effective heat transfer coefficient (eK) is a value thatcan be obtained by measuring a total heat transfer amount and atemperature at least one portion at which heat is transferred. Forexample, a calorific value (W) is measured using a heating source thatcan be quantitatively measured in the refrigerator, a temperaturedistribution (K) of the door is measured using heats respectivelytransferred through a main body and an edge of the door of therefrigerator, and a path through which heat is transferred is calculatedas a conversion value (m), thereby evaluating an effective heat transfercoefficient.

The effective heat transfer coefficient (eK) of the entire vacuumadiabatic body is a value given by k=QL/AΔT. Here, Q denotes a calorificvalue (W) and may be obtained using a calorific value of a heater. Adenotes a sectional area (m²) of the vacuum adiabatic body, L denotes athickness (m) of the vacuum adiabatic body, and ΔT denotes a temperaturedifference.

For the surface conduction heat, a conductive calorific value may beobtained through a temperature difference (ΔT) between an entrance andan exit of the conductive resistance sheet 60 or 63, a sectional area(A) of the conductive resistance sheet, a length (L) of the conductiveresistance sheet, and a thermal conductivity (k) of the conductiveresistance sheet (the thermal conductivity of the conductive resistancesheet is a material property of a material and can be obtained inadvance). For the supporter conduction heat, a conductive calorificvalue may be obtained through a temperature difference (ΔT) between anentrance and an exit of the supporting unit 30, a sectional area (A) ofthe supporting unit, a length (L) of the supporting unit, and a thermalconductivity (k) of the supporting unit. Here, the thermal conductivityof the supporting unit is a material property of a material and can beobtained in advance. The sum of the gas conduction heat {circle around(3)}, and the radiation transfer heat {circle around (4)} may beobtained by subtracting the surface conduction heat and the supporterconduction heat from the heat transfer amount of the entire vacuumadiabatic body. A ratio of the gas conduction heat {circle around (3)},and the radiation transfer heat {circle around (4)} may be obtained byevaluating radiation transfer heat when no gas conduction heat exists byremarkably lowering a vacuum degree of the vacuum space part 50.

When a porous substance is provided inside the vacuum space part 50,porous substance conduction heat {circle around (5)} may be a sum of thesupporter conduction heat {circle around (2)} and the radiation transferheat {circle around (1)}. The porous substance conduction heat {circlearound (5)} may be changed depending on various variables including akind, an amount, and the like of the porous substance.

According to an embodiment, a temperature difference ΔT₁ between ageometric center formed by adjacent bars 31 and a point at which each ofthe bars 31 is located may be preferably provided to be less than 0.5°C. Also, a temperature difference ΔT₂ between the geometric centerformed by the adjacent bars 31 and an edge portion of the vacuumadiabatic body may be preferably provided to be less than 0.5° C. In thesecond plate member 20, a temperature difference between an averagetemperature of the second plate and a temperature at a point at which aheat transfer path passing through the conductive resistance sheet 60 or63 meets the second plate may be largest. For example, when the secondspace is a region hotter than the first space, the temperature at thepoint at which the heat transfer path passing through the conductiveresistance sheet meets the second plate member becomes lowest.Similarly, when the second space is a region colder than the firstspace, the temperature at the point at which the heat transfer pathpassing through the conductive resistance sheet meets the second platemember becomes highest.

This means that the amount of heat transferred through other pointsexcept the surface conduction heat passing through the conductiveresistance sheet should be controlled, and the entire heat transferamount satisfying the vacuum adiabatic body can be achieved only whenthe surface conduction heat occupies the largest heat transfer amount.To this end, a temperature variation of the conductive resistance sheetmay be controlled to be larger than that of the plate member.

Physical characteristics of the parts constituting the vacuum adiabaticbody will be described. In the vacuum adiabatic body, a force by vacuumpressure is applied to all of the parts. Therefore, a material having astrength (N/m²) of a certain level may be preferably used.

Under such circumferences, the plate members 10 and 20 and the sideframe 70 may be preferably made of a material having a sufficientstrength with which they are not damaged by even vacuum pressure. Forexample, when the number of bars 31 is decreased so as to limit thesupport conduction heat, deformation of the plate member occurs due tothe vacuum pressure, which may have a bad influence on the externalappearance of refrigerator. The radiation resistance sheet 32 may bepreferably made of a material that has a low emissivity and can beeasily subjected to thin film processing. Also, the radiation resistancesheet 32 is to ensure a strength strong enough not to be deformed by anexternal impact. The supporting unit 30 is provided with a strengthstrong enough to support the force by the vacuum pressure and endure anexternal impact, and is to have machinability. The conductive resistancesheet 60 may be preferably made of a material that has a thin plateshape and can endure the vacuum pressure.

In an embodiment, the plate member, the side frame, and the conductiveresistance sheet may be made of stainless materials having the samestrength. The radiation resistance sheet may be made of aluminum havinga weaker strength that the stainless materials. The supporting unit maybe made of resin having a weaker strength than the aluminum.

Unlike the strength from the point of view of materials, analysis fromthe point of view of stiffness is required. The stiffness (N/m) is aproperty that would not be easily deformed. Although the same materialis used, its stiffness may be changed depending on its shape. Theconductive resistance sheets 60 or 63 may be made of a material having astrength, but the stiffness of the material is preferably low so as toincrease heat resistance and minimize radiation heat as the conductiveresistance sheet 60 or 63 is uniformly spread without any roughness whenthe vacuum pressure is applied. The radiation resistance sheet 32requires a stiffness of a certain level so as not to contact anotherpart due to deformation. Particularly, an edge portion of the radiationresistance sheet 32 may generate conduction heat due to drooping causedby the self-load of the radiation resistance sheet. Therefore, astiffness of a certain level is required. The supporting unit 30requires a stiffness to endure a compressive stress from the platemember and an external impact.

In an embodiment, the plate member and the side frame may preferablyhave the highest stiffness so as to prevent deformation caused by thevacuum pressure. The supporting unit, particularly, the bar maypreferably have the second highest stiffness. The radiation resistancesheet may preferably have a stiffness that is lower than that of thesupporting unit but higher than that of the conductive resistance sheet.The conductive resistance sheet may be preferably made of a materialthat is easily deformed by the vacuum pressure and has the loweststiffness.

Even when the porous substance 33 is filled in the vacuum space part 50,the conductive resistance sheet may preferably have the loweststiffness, and the plate member and the side frame may preferably havethe highest stiffness.

Hereinafter, a vacuum pressure preferably determined depending on aninternal state of the vacuum adiabatic body will be described. Asalready described above, a vacuum pressure is to be maintained insidethe vacuum adiabatic body so as to reduce heat transfer. At this time,it will be easily expected that the vacuum pressure is preferablymaintained as low as possible so as to reduce the heat transfer.

The vacuum space part may resist the heat transfer by applying only thesupporting unit 30. Alternatively, the porous substance 33 may be filledtogether with the supporting unit in the vacuum space part 50 to resistthe heat transfer. Alternatively, the vacuum space part may resist theheat transfer not by applying the supporting unit but by applying theporous substance 33.

The case where only the supporting unit is applied will be described.

FIG. 5 illustrates graphs showing changes in adiabatic performance andchanges in gas conductivity with respect to vacuum pressures by applyinga simulation.

Referring to FIG. 5 , it can be seen that, as the vacuum pressure isdecreased, i.e., as the vacuum degree is increased, a heat load in thecase of only the main body (Graph 1) or in the case where the main bodyand the door are joined together (Graph 2) is decreased as compared withthat in the case of the typical product formed by foaming polyurethane,thereby improving the adiabatic performance. However, it can be seenthat the degree of improvement of the adiabatic performance is graduallylowered. Also, it can be seen that, as the vacuum pressure is decreased,the gas conductivity (Graph 3) is decreased. However, it can be seenthat, although the vacuum pressure is decreased, the ratio at which theadiabatic performance and the gas conductivity are improved is graduallylowered. Therefore, it is preferable that the vacuum pressure isdecreased as low as possible. However, it takes long time to obtainexcessive vacuum pressure, and much cost is consumed due to excessiveuse of a getter. In the embodiment, an optimal vacuum pressure isproposed from the above-described point of view.

FIG. 6 illustrates graphs obtained by observing, over time and pressure,a process of exhausting the interior of the vacuum adiabatic body whenthe supporting unit is used.

Referring to FIG. 6 , in order to create the vacuum space part 50 to bein the vacuum state, a gas in the vacuum space part 50 is exhausted by avacuum pump while evaporating a latent gas remaining in the parts of thevacuum space part 50 through baking. However, if the vacuum pressurereaches a certain level or more, there exists a point at which the levelof the vacuum pressure is not increased any more (Δt1). After that, thegetter is activated by disconnecting the vacuum space part 50 from thevacuum pump and applying heat to the vacuum space part 50 (Δt2). If thegetter is activated, the pressure in the vacuum space part 50 isdecreased for a certain period of time, but then normalized to maintaina vacuum pressure of a certain level. The vacuum pressure that maintainsthe certain level after the activation of the getter is approximately1.8×10⁻⁶ Torr.

In the embodiment, a point at which the vacuum pressure is notsubstantially decreased any more even though the gas is exhausted byoperating the vacuum pump is set to the lowest limit of the vacuumpressure used in the vacuum adiabatic body, thereby setting the minimuminternal pressure of the vacuum space part 50 to 1.8×10⁻⁶ Torr.

FIG. 7 illustrates graphs obtained by comparing vacuum pressures and gasconductivities.

Referring to FIG. 7 , gas conductivities with respect to vacuumpressures depending on sizes of a gap in the vacuum space part 50 arerepresented as graphs of effective heat transfer coefficients (eK).Effective heat transfer coefficients (eK) were measured when the gap inthe vacuum space part 50 has three sizes of 2.76 mm, 6.5 mm, and 12.5mm. The gap in the vacuum space part 50 is defined as follows. When theradiation resistance sheet 32 exists inside vacuum space part 50, thegap is a distance between the radiation resistance sheet 32 and theplate member adjacent thereto. When the radiation resistance sheet 32does not exist inside vacuum space part 50, the gap is a distancebetween the first and second plate members.

It can be seen that, since the size of the gap is small at a pointcorresponding to a typical effective heat transfer coefficient of 0.0196W/mK, which is provided to a adiabatic material formed by foamingpolyurethane, the vacuum pressure is 2.65×10⁻¹ Torr even when the sizeof the gap is 2.76 mm. Meanwhile, it can be seen that the point at whichreduction in adiabatic effect caused by gas conduction heat is saturatedeven though the vacuum pressure is decreased is a point at which thevacuum pressure is approximately 4.5×10⁻³ Torr. The vacuum pressure of4.5×10⁻³ Torr can be defined as the point at which the reduction inadiabatic effect caused by gas conduction heat is saturated. Also, whenthe effective heat transfer coefficient is 0.1 W/mK, the vacuum pressureis 1.2×10⁻² Torr.

When the vacuum space part 50 is not provided with the supporting unitbut provided with the porous substance, the size of the gap ranges froma few micrometers to a few hundreds of micrometers. In this case, theamount of radiation heat transfer is small due to the porous substanceeven when the vacuum pressure is relatively high, i.e., when the vacuumdegree is low. Therefore, an appropriate vacuum pump is used to adjustthe vacuum pressure. The vacuum pressure appropriate to thecorresponding vacuum pump is approximately 2.0×10⁻⁴ Torr. Also, thevacuum pressure at the point at which the reduction in adiabatic effectcaused by gas conduction heat is saturated is approximately 4.7×10⁻²Torr. Also, the pressure where the reduction in adiabatic effect causedby gas conduction heat reaches the typical effective heat transfercoefficient of 0.0196 W/mK is 730 Torr.

When the supporting unit and the porous substance are provided togetherin the vacuum space part, a vacuum pressure may be created and used,which is between the vacuum pressure when only the supporting unit isused and the vacuum pressure when only the porous substance is used.

Hereinafter, the supporting unit 30 using the porous substance that hasbeen proposed through FIG. 3 c will be described in detail.

FIG. 8 is a sectional view of a vacuum adiabatic body according to anembodiment, which schematically shows the vacuum adiabatic bodyavailable for the main body of the refrigerator.

Referring to FIG. 8 , a porous substance package 80 is inserted betweena first plate member 10 and a second plate member 20. The poroussubstance package 80 includes first, second, and third porous substancepackages 801, 802, and 803 respectively into both side portions and arear portion. An exhaust port 40 and a getter port 41 are provided atone side of the first plate member 10. A conductive resistance sheet 60is provided at a place at which the first plate member 10 and the secondplate member 20 meet each other, to resist heat conduction between theplate members 10 and 20.

The porous substance package 80 may be provided in a form in which aporous substance is placed thereinside, and the outside of the poroussubstance package 80 is surrounded by a film. In a state in which theporous substance package 80 is inserted between the plate members 10 and20, a predetermined hole may be provided in the film such that theinside and outside of the film communicate with each other.

The hole has not been provided since the porous substance package 80 wasfabricated, and may be generated as the vacuum adiabatic body isfabricated by inserting the porous substance package 80 between theplate members 10 and 20. A material having a low outgassing rate may bepreferably used as the film, to prevent degradation of vacuum degree,which may occur as the film is used. The film may be provided in asingle layer. The hole is provided in a film that is minute in size andthin in thickness, and therefore, its illustration is omitted.

FIG. 9 is a view sequentially illustrating a fabrication method of thevacuum adiabatic body when a porous substance is used.

First, referring to FIG. 9 a , the porous substance packages 801, 802,and 803 are disposed inside the second plate member 20. The poroussubstance package 80 may be provided in a panel shape, and therefore,three porous substance packages may be respectively placed at cornersprovided by the second plate member 20. When the vacuum adiabatic bodyis provided in the door, a single vacuum adiabatic body provided in aplate shape may be sufficiently used.

The inside of the porous substance package is provided to be in a vacuumstate, which may be referred to as a temporarily vacuumed state, ascompared with an additional vacuuming process which will be describedlater. The porous substance package 80 in this state may be referred toas a temporarily vacuumed porous substance package.

The temporary vacuum state may mean that pressure is lower thanatmospheric pressure, i.e., that a vacuum degree is provided at acertain level. This is because a vacuum pressure of temporary vacuumrequired in the temporarily vacuumed porous substance package issufficient as a pressure at which any additional deformation does notoccur. In other words, the vacuum pressure of temporary vacuum may beprovided as a pressure at which the fabrication efficiency of the poroussubstance package is improved, and there is no problem about deformationof the vacuum adiabatic body due to an additional decrease in volumewhen the porous substance package is mounted in the vacuum adiabaticbody. That is, the vacuum pressure of temporary vacuum may be providedas a pressure lower than the atmospheric pressure. In this case, thevacuum pressure may be provided as a pressure higher than the pressureof the vacuum adiabatic body. Accordingly, it is possible to reduce thetime required to fabricate the porous substance package 80.

FIG. 10 is a sectional view of a porous substance package temporarilyvacuumed before being mounted in the vacuum adiabatic body.

Referring to FIG. 10 , the porous substance package 80 may be providedin the structure of a film 34 by which a porous substance 33 isaccommodated. A fusion part or fused portion 81 is provided at endportions of the film 34, so that, after the porous material 33 isaccommodated by the film 34 and then sealed, a large amount of matter isnot introduced into the porous substance 33 from the outside of the film34.

The porous substance 33 may include glass wool that has no outgassingand allows its density to be changed.

The inside of the porous substance package 80 is provided in the vacuumstate, so that the porous substance package 80 can be easily mounted ina gap part or gap between the plate members 10 and 20. In addition, anadditional deformation of the porous substance package 80 hardly occursafter the porous substance package 80 is mounted in the gap part. If theporous substance package 80 is placed in the gap part between the platemembers 10 and 20 in a state that is not the vacuum state, the volume ofthe porous substance package 80 is increased, and therefore, fasteningbetween the plate members 10 and 20 is difficult. In addition, as avacuum space part 50 is contracted in creation of the vacuum state,deformation of the vacuum adiabatic body may occur, which is notpreferable.

The film 34 may include thin-film PE that has a small amount ofoutgassing, easily provides a hole due to heat or impact, has excellentmachinability, and is easily deformed. Since a hole is to be machined ina subsequent process, the film 34 may be provided as a thin film. Whenthe film 34 is provided as a thin film, it is impossible to completelyblock introduction of gas and liquid from the outside. Therefore, afterthe porous substance package 80 is provided to be in the vacuum state,the porous substance package 80 is more preferably applied to the vacuumadiabatic body within a certain period of time.

In order to block gas and liquid, which pass through the film 34, thefilm 34 may be provided to have a predetermined thickness or more usinga metal thin film such as aluminum or a specific resin. However, whenthe metal thin film is used, the adiabatic effect of the vacuumadiabatic body is rapidly decreased due to heat conduction through themetal thin film. Therefore, the metal thin film cannot be used in thevacuum adiabatic body of the embodiment. When the specific resin isused, cost is increased. When the film 34 is provided to having apredetermined thickness or more, it is difficult to provide a hole in asubsequent process, which is not preferable.

The film 34 may be provided to have a thickness of 1 to 100 μm byconsidering such conditions, such as temperature in a gettering process,and the like. This is because, if the thickness of the film 34 isextremely thick, it is difficult to provide a hole in the film 34 in asubsequent process, and, if the thickness of the film 34 is extremelythin, it is difficult to provide the fusion part 81.

FIG. 11 is a view illustrating a fabrication apparatus of the poroussubstance package.

Referring to FIG. 11 , a case 101 capable of providing a vacuum space isprovided. The porous substance 33 is provided to a package frame 102provided in the vacuum space of the case 101 in a state in which theporous substance 33 is accommodated by the film 34. In addition, avacuum pressure is provided by operating a pump 105 and opening a valve104. The package frame 102 may function to compress the porous substance33. After the vacuum pressure of an internal space of the film 34 isprovided at a certain level or less, the internal space of the film 34is sealed by fusing an entry part 341 of the film 34, which is placed inthe fusion frame 103.

Since the film 34 is provided as a thin film, an unfused portion may begenerated when the entry part 341 is melted and fused to form the fusionpart 81. In this case, the internal space of the film 34 may not becreated to have the vacuum pressure. In order to solve this problem,another embodiment of the porous substance package will be describedwith reference to FIGS. 13 and 14 .

Referring to FIG. 13 , the entry part 341 may be provided thicker thanother portions. In this case, two portions of the entry part 341, whichare opposite to each other, provide liquid resin when they are meltedand fused, and hence can be completely fused to each other. Referring toFIG. 14 , a metal thin film 342 may be provided to the entry part 341 atthe outside of the film 34. In this case, the fusion part 81 can becompletely provided by an action in which the metal thin film 342supports the entry part 341.

Referring back to FIG. 9 c , the first plate member 10 is put inside theporous substance package 80. The getter port 41 into which a getter 43is inserted is provided to the first plate member 10, to further improvea vacuum environment inside the vacuum space part 50 through asubsequent activation process. In addition, the exhaust port 40 isfurther provided to the first plate member 10, to further improve avacuum degree inside the vacuum space part 50 inside which the poroussubstance package 80 is accommodated.

Referring to FIG. 9 d , a process of fastening the plate members 10 and20 to each other may be performed. At this time, the conductiveresistance sheet 60 is provided at a fastened portion to resist heatconduction between the plate members 10 and 20. The conductiveresistance sheet 60 and the plate members 10 and 20 may be fastened toeach other through welding. Here, the porous substance is filled in thevacuum space part 50, and hence the conductive resistance sheet 60 maybe provided in a planar shape instead of the curved shape described inthe aforementioned embodiment.

If the conductive resistance sheet 60 is fastened, the inside of thevacuum adiabatic body may be provided as a closed space separated fromthe exterior. After that, a process of providing the inside of thevacuum adiabatic body to be in the vacuum state is performed.

Referring to FIG. 9 e , there is performed a process of exhausting airinside the vacuum adiabatic body by connecting a vacuum pump to theexhaust port 40. When the exhausting process is performed, heat isapplied to the vacuum adiabatic body, so that it is possible toevaporate a liquid component that may remain inside the vacuum adiabaticbody. In addition, it is possible to activate a gas inside the vacuumadiabatic, thereby further decreasing the vacuum pressure inside thevacuum adiabatic body. Meanwhile, as a melted portion may be generatedin the film 34 of the porous substance package 80 by the applied heat inthe exhausting process, a hole may be provided. A gas or liquidcomponent existing in the temporarily vacuumed porous substance package80 may be exhausted through the hole. In addition, after the temporarilyvacuumed porous substance package 80 is fabricated, a gas or liquidcomponent infiltrated by passing through the film 34 may also beexhausted through the hole. Through the hole provided in the film 34,the vacuum degree of the vacuum space part 50 can be entirely equalizedwithout any difference between the interior and exterior.

Referring to FIG. 9F, as the operation of the vacuum pump is ended byclosing a valve, the exhaust port 40 can be sealed. In addition, thegetter 43 is activated, thereby further improving the vacuum degree ofthe vacuum space part 50.

Meanwhile, the process of punching the hole in the film 34 of thetemporarily vacuumed porous substance package 80 is an important processfor discharging a matter infiltrated into the porous substance package80. This is required to consider the mobility of the temporarilyvacuumed porous substance package and to improve productivity.Therefore, the hole is to be punched or punctured in the film 34 of thetemporarily vacuumed porous substance package 80 while any one of theexhausting process and the gettering process is being performed. It willbe apparent that the hole may be provided as the film 34 is melted byheat. However, a punching or puncture mechanism may be provided at anyone side of the plate members 10 and 20 so as to provide against a casewhere the film is not punched even by heat and to accurately perform theprocess of punching the hole in the film. However, even when the hole isnot provided, the function of the vacuum adiabatic body itself may beperformed.

FIG. 12 is a view showing an embodiment of the punching mechanism.

The punching mechanism may include a deforming part 803 provided at apredetermined position of each of the plate members 10 and 20 and a pin804 provided on an inner surface of the deforming part 803. Thedeforming part 803 may be provided in a shape protruding outward fromeach of the plate members 10 and 20. Therefore, when the deforming part803 is introduced into the vacuum space part 50 by a force with which apressure difference between the vacuum pressure and the atmosphericpressure is applied to the deforming part 803 as the vacuum pressure ofthe vacuum space part 50 is lowered, the pin 804 pierces the film 34,thereby providing the hole.

The deforming part 803 may be provided at any point of a portion atwhich each of the plate member 10 and 20 contacts the film 34. Thedeforming part 803 allows the thickness of each of the plate members 10and 20 to be decreased by pressing the plate member. Thus, although theplate member is pressed by the force of the atmospheric pressure,deformation of the deforming part 803 can occur.

The vacuum adiabatic body on which the function of the supporting unitis performed can be provided as the vacuum space part is filled with theporous substance through the processes proposed in FIG. 9 .

Meanwhile, the getter port 41 may be provided to each of the platemembers 10 and 20 as described in the embodiment, but may be provided tothe porous substance package 80. Specifically, when the getter port 41is provided to each of the plate members 10 and 20, the getter is not inthe vacuum state, and hence the volume of the getter 43 may be decreasedas the exhaust process is performed. In this case, the volume of aportion at which the getter 43 is placed is changed as well as thevolume of the getter 43, and therefore, there may occur a problem suchas disagreement of dimensions of the vacuum adiabatic body. This maydeepen a problem that deformation of each of the plate members 10 and 20may slightly occur in the embodiment in which the temporarily vacuumedporous substance package is used.

In order to solve the problem of the deformation of the plate member,the getter may be previously provided inside the porous substancepackage, i.e., inside the film 34. In this case, an environment ofvacuum pressure is created with respect to the getter during the processof temporarily vacuuming the porous substance package, thereby solvingthe problem of the deformation of the plate member. However, when thegetter is located inside the porous substance package, the performanceof the getter may be deteriorated due to gas and liquid, which may beinfiltrated into the temporarily vacuumed porous substance package for atime required to have the temporarily vacuumed porous package to bebuilt in the vacuum adiabatic body after the temporarily vacuumed porouspackage is fabricated. Therefore, the vacuum degree of the temporarilyvacuumed porous package is to be further increased. In order to furtherdecrease the vacuum degree of the temporarily vacuumed porous package,the time required to operate the vacuum pump is to be further increased,which results in inefficiency of fabrication processes and an increasein fabrication cost.

Under such circumferences, the getter may be provided to at least one orboth of the plate member and the porous substance package depending on ause place or required performance of the vacuum adiabatic body.

If the porous substance is used for a supporting unit, it is possible tosolve problems such as a problem of weight, which caused in the case ofthe supporting unit 30 including the bar 31, a problem of difficulty indesigning the strength of the supporting unit, a problem of loss of heatpassing through the bar, and a problem of failure of the entiresupporting unit due to concentration of stress on another bar when anyone bar is damaged.

As another embodiment, when only the porous substance is provided in theporous substance package, a support structure corresponding to the bar31 may be additionally provided inside the porous substance package whenit is likely that deformation of the plate member will seriously occur,thereby preventing the deformation of the plate member.

In the description of the present disclosure, a part for performing thesame action in each embodiment of the vacuum adiabatic body may beapplied to another embodiment by properly changing the shape ordimension of the other embodiment. Accordingly, still another embodimentcan be easily proposed. For example, in the detailed description, in thecase of a vacuum adiabatic body suitable as a door-side vacuum adiabaticbody, the vacuum adiabatic body may be applied as a main body-sidevacuum adiabatic body by properly changing the shape and configurationof a vacuum adiabatic body.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

The vacuum adiabatic body proposed in the present disclosure may bepreferably applied to refrigerators. However, the application of thevacuum adiabatic body is not limited to the refrigerators, and may beapplied in various apparatuses such as cryogenic refrigeratingapparatuses, heating apparatuses, and ventilation apparatuses.

According to the present disclosure, the vacuum adiabatic body can beindustrially applied to various adiabatic apparatuses. The adiabaticeffect can be enhanced, so that it is possible to improve energy useefficiency and to increase the effective volume of an apparatus.

However, it is difficult to obtain an adiabatic effect of a practicallevel by providing the walls of the refrigerator to be in a sufficientvacuum state. Specifically, it is difficult to prevent heat transfer ata contact portion between external and internal cases having differenttemperatures.

Further, it is difficult to maintain a stable vacuum state. Furthermore,it is difficult to prevent deformation of the cases due to a soundpressure in the vacuum state. Due to these problems, the technique ofReference Document 3 is limited to cryogenic refrigerating apparatuses,and is not applied to refrigerating apparatuses used in generalhouseholds.

Embodiments provide a vacuum adiabatic body, a fabrication method forthe vacuum adiabatic body, a porous substance package, and arefrigerator, which can obtain a sufficient adiabatic effect in a vacuumstate and be applied commercially.

In one embodiment, a vacuum adiabatic body includes: a first platemember or first plate defining at least one portion of a wall for afirst space; a second plate member or second plate defining at least oneportion of a wall for a second space having a different temperature fromthe first space; a sealing part or seal sealing the first plate memberand the second plate member to provide a third space that has atemperature between the temperature of the first space and thetemperature of the second space and is in a vacuum state; a supportingunit or support maintaining the third space; a heat resistance unit ordevice for decreasing a heat transfer amount between the first platemember and the second plate member; and an exhaust port through which agas in the third space is exhausted, wherein the supporting unitincludes: a porous substance; and a film made of a resin material, thefilm accommodating the porous substance thereby.

The supporting unit may be provided only with the porous substance andthe film made of the resin material. The film made of the resin materialmay be provided in a single layer. At least one hole may be provided inthe film. A thickness of the film may be 1 to 100 μm. The vacuumadiabatic body may further include a punching mechanism for punching thefilm.

In another embodiment, a porous substance package includes: a poroussubstance; and a film providing a space in which the porous substance isaccommodated by separating the porous substance from an outside thereof,wherein the porous substance package allows an external gas or liquid tobe introduced into the porous substance by passing through the film.

The film may be provided in a single layer. The porous substance packagemay include a fusion part or fused portion provided by fusing an entrypart through which the porous substance is accommodated by the film. Thefusion part may be provided thicker than other portions, or a metal thinfilm may be provided to the fusion part. The porous substance packagemay include a getter provided thereinside.

In still another embodiment, a fabrication method for a vacuum adiabaticbody includes: accommodating a porous substance package in a vacuumstate in an internal space of an environment closed from the exterior;exhausting air in the internal space; and exploding or releasing theporous substance package such that the entire pressure of the internalspace is equalized.

The porous substance package may include a porous substance and a filmaccommodating the porous substance thereby. In the exhausting of theair, heat may be applied, and the film may be melted by the heat,thereby exploding the porous substance package.

A punching mechanism for exploding the porous substance package may befurther provided.

In still another embodiment, a refrigerator includes: a main bodyprovided with an internal space in which storage goods are stored; and adoor provided to open/close the main body from an external space,wherein, in order to supply a refrigerant into the main body, therefrigerator includes: a compressor for compressing the refrigerant; acondenser for condensing the compressed refrigerant; an expander forexpanding the condensed refrigerant; and an evaporator for evaporatingthe expanded refrigerant to take heat, wherein at least one of the mainbody and the door includes a vacuum adiabatic body, wherein the vacuumadiabatic body includes: a first plate member or first plate defining atleast one portion of a wall for the internal space; a second platemember or second plate defining at least one portion of a wall for theexternal space; a sealing part or seal sealing the first plate memberand the second plate member to provide a vacuum space part or vacuumspace that has a temperature between a temperature of the internal spaceand a temperature of the external space and is in a vacuum state; asupporting unit or support maintaining the vacuum space part; a heatresistance unit or device for decreasing a heat transfer amount betweenthe first plate member and the second plate member; and an exhaust portthrough which a gas in the vacuum space part is exhausted, wherein thevacuum space part is provided with a porous substance package includinga porous substance and a punched film accommodating the porous substancethereby.

The porous substance may be provided in supporting unit. The film may bemade of PE, and the porous material may be made of glass wool. When thevacuum adiabatic body is provided in the main body, the porous substancepackage may be provided in at least three. A bar may be provided in theporous substance package. The film may be provided in a single layer.The refrigerator may include a pin protruding to an inside of the vacuumspace part.

According to the present disclosure, it is possible to obtain asufficient and stable vacuum adiabatic effect. According to the presentdisclosure, it is possible to perform heat insulation on the vacuumspace part. According to the present disclosure, it is possible toprovide a vacuum adiabatic body applicable to apparatuses such asrefrigerators at low cost through a simple process.

The details of one or more embodiments are set forth in the accompanyingdrawings and the description below. Other features will be apparent fromthe description and drawings, and from the claims.

Any reference in this specification to “one embodiment,” “anembodiment,” “example embodiment,” etc., means that a particularfeature, structure, or characteristic described in connection with theembodiment is included in at least one embodiment of the invention. Theappearances of such phrases in various places in the specification arenot necessarily all referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with any embodiment, it is submitted that it is within thepurview of one skilled in the art to effect such feature, structure, orcharacteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A vacuum adiabatic body comprising: a first plateto have a first temperature; a second plate to have a second temperaturedifferent from the first temperature; a seal configured to seal thefirst plate and the second plate, and to provide a space that has athird temperature, the space to be provided into a vacuum state; aporous substance to be disposed within the space; a film configured toaccommodate the porous substance; and an exhaust port configured toexhaust air from within the space, wherein the air exhausted through theexhaust port includes air inside of the film.
 2. The vacuum adiabaticbody of claim 1, wherein the porous substance has a higher emissivitythan material of the first and second plates.
 3. The vacuum adiabaticbody of claim 1, wherein the porous substance is provided in a statesurrounded by the film.
 4. The vacuum adiabatic body of claim 1,comprising a support that supports the first and second plates and isprovided in the space.
 5. The vacuum adiabatic body of claim 1, whereinthe film is provided in a single layer.
 6. The vacuum adiabatic body ofclaim 1, wherein the film is made of a resin material such that theporous substance does not pass through the resin material and anexternal gas or liquid passes through the resin material.
 7. The vacuumadiabatic body of claim 1, wherein at least one hole is provided in thefilm such that the porous substance passes through the at least onehole.
 8. The vacuum adiabatic body of claim 1, wherein the film has athickness of 1 to 100 μm.
 9. The vacuum adiabatic body of claim 1,comprising a punching mechanism for puncturing the film.
 10. Arefrigerator comprising: a main body having an internal space to storegoods; and a door configured to open and close the main body from anexternal space, wherein, in order to supply a refrigerant into the mainbody, the refrigerator comprises: a compressor that compresses therefrigerant; a condenser that condenses the compressed refrigerant; anexpander that expands the condensed refrigerant; and an evaporator thatevaporates the expanded refrigerant, wherein at least one of the mainbody and the door comprises the vacuum adiabatic body of claim
 1. 11. Avacuum adiabatic body comprising: a first plate to have a firsttemperature; a second plate to have a second temperature different fromthe first temperature; a seal configured to seal the first plate and thesecond plate, and to provide a space that has a third temperature, thespace to be provided into a vacuum state; an exhaust port configured toexhaust an air from within the space; and a porous substance package tobe provided within the space, the porous substance package comprising aporous substance and a punctured film configured to accommodate theporous substance therein.
 12. A refrigerator comprising: a main bodyhaving an internal space to store goods; and a door configured to openand close the main body from an external space, wherein, in order tosupply a refrigerant into the main body, the refrigerator comprises: acompressor that compresses the refrigerant; a condenser that condensesthe compressed refrigerant; an expander that expands the condensedrefrigerant; and an evaporator that evaporates the expanded refrigerant,wherein at least one of the main body and the door comprises the vacuumadiabatic body of claim
 11. 13. The vacuum adiabatic body of claim 11,wherein the punctured film includes a hole to communicate between insideand outside of the film.
 14. The vacuum adiabatic body of claim 11,wherein the film is provided in a single layer.
 15. The vacuum adiabaticbody of claim 11, wherein the porous substance includes glass wool. 16.The vacuum adiabatic body of claim 11, wherein the film has a thicknessof 1 to 100 μm.
 17. The vacuum adiabatic body of claim 11, comprising apunching mechanism for puncturing the film.
 18. A vacuum adiabatic bodycomprising: a first plate to have a first temperature; a second plate tohave a second temperature different from the first temperature; a sealconfigured to seal the first plate and the second plate, and to providea space that has a third temperature, and the space is to be providedwithin a vacuum state; a porous substance to be disposed inside of thespace; a film configured to accommodate the porous substance therein;and an exhaust port configured to exhaust air from within the space,wherein based on the exhaust port exhausting the air, the film is tomelt by heat or the film is punched, thereby releasing the poroussubstance into the space.
 19. The vacuum adiabatic body of claim 18,wherein the exhaust port is provided at the first plate.
 20. The vacuumadiabatic body of claim 18, comprising a getter port provided at thefirst plate.